For the first time in days, I watched solid water melt into liquid in the open air. I’d only witnessed the reverse process since we’d started mushing three days before. Fire roared in front of me, fueled by pieces of split jackpine and black spruce. The night was finally warm enough to liberate us from the canvas wall tent, and we cooked and ate beneath the dark sky. Flakes fell steadily and melted where they landed on my legs, enough to dampen the windproof nylon above my knees. I marveled at the warm night. Our thermometer read 3°F.

Some aspects of temperature are absolute. Molecular motion stops at -460°F. Human organs require a core body temperature of 98.6°F for optimal function. Pure water freezes at 32°F and boils at 212°F, assuming standard pressure. Our perception of temperature, however, is wildly relative. Our snowy night on Thomas Lake was the first time…